Machines employing article raising elevators



March 1966 c. o. MERCHANT ETAL 3,243,033

MACHINES EMPLOYING ARTICLE RAISING ELEVATORS Filed Feb. 18, 1964 5 Sheets-Sheet 1 INVENTORS CHEJTL'R a. MA HANT WILL/AM HOPP March 29, 1966 c. o. MERCHANT ETAL 3,243,033 Filed Feb. 18, 1964 5 Sheets-Sheet Z INVENTORJ STER o. MERCHANT LIAM HOPPE CH5 W/L BY March 29, 1966 c. o. MERCHANT ETAL 3,243,033

MACHINES EMPLOYING ARTICLE RAISING ELEVATORS Filed Feb. 18, 1964 5 Sheets-$heet 3 March 1966 c. o. MERCHANT ETAL 3,243,033

MACHINES EMPLOYING ARTICLE RAISING ELEVATORS Filed Feb. 18, 1964 5 SheetsSheet 4 INVENTORS CHESTER 0. MERCHANT W/LL [AM HOPPf.

Mamh 1966 c. o. MERCHANT ETAL 3,

MACHINES EMPLOYING ARTICLE RAISING ELEVATORS Filed Feb. 18, 1964 5 Sheets-Sheet 5 INVENTORS CHESTER O. MERCHA N W/LL IA M HOPP Mm S United States Patent 3,243,033 MACHINES EMPLOYING ARTICLE RAISING ELEVATORS Chester 0. Merchant, East Longrneadow, and William Hoppe, Longmeadow, Mass, assignors to Package Machinery Company, East Longmeadow, Mass., a corporation of Massachusetts Filed Feb. 18, 1964, Ser. No. 345,733 7 Claims. (Cl. 198-106) The present invention relates to improvements in machines of the type employing an elevator for raising successive articles to a higher level, as in wrapping or stacking of articles.

One objectof the invention is to overcome the prior limitation that the maximum rate of operation of such machines is automatically established by the design limits for the highest, i.e. tallest article, and to economically pro-.

vide for higher rates of-operation where articles of lesser height are being handled and thereby .obtain the maximum possible rate of operation for any given height of article.

Another object is to provide for a minimum changeover time for different height articles to obtain such maximum operating rates.

A further object of the invention is to provide an im proved and easily adjustable mechanism for raising articles a variable distance to a fixed discharge position.

Machines of the present invention are characterized by an elevator which reciprocates between a lower article receiving position and an upper discharge position, and a conveyor which feeds successive articles onto the elevator which then raises them to the discharge position. In accordance with the invention, means are provided for varying the stroke of the elevator to the minimum necessary for a given height of article, while at the same time maintaining the upper discharge position of the elevator at a constant level. In combination with this, means are provided for varying the height of the feed conveyor to properly feed articles onto the elevator in its lower position. Advantageously, these adjustments may be operated by a common control element.

With the stroke of the elevator maintained at a minimum for any given height of article, it is then possible to employ means for varying the rate of operation of the machine to obtain the maximum possible rate which, by and large, is dependent upon the length of stroke of the elevator.

Another feature of the invention is found in the provision of change gears which enable the number of reciprocations of the elevator to be varied relative to the cyclic operation of the machine.

Another characterizing feature of the invention is in the means for varying the elevator stroke. These means comprise an oscillatable lever connected to impart reciprocable movement to the elevator. This lever is slidably mounted on a block which in turn is pivotally mounted. Means are provided for adjusting this pivotal axis in a direction parallel to the lever in the upper position thereof. By so doing, the upper position of the elevator is maintained a constant while its stroke is varied.

The above and other related objects and features of the invention will be apparent from a reading of the following description of the disclosure found in the accompanying drawings and the novelty thereof pointed out in the appended claims.

In the drawings:

FIG. 1 is a perspective view diagrammatically illustrating one embodiment of the invention;

FIG. 2 is a perspective view diagrammatically illustrating another embodiment of the invention;

FIG. 3 is an elevation illustrating in detail, with pertions broken away and in section, elevator reciprocating mechanism employed herein;

FIG. 4 is a plan view of the elevator reciprocating mechanism;

FIG. 5 is a section on an enlarged scale taken on line VV in FIG. 3;

FIG. 6 is a section taken on line VI-VI in FIG. 4;

FIG. 7 is a view taken on line VIIVII in FIG. 4 diagrammatically illustrating the position of an actuating lever in two extreme positions; and

FIG. 8 is a view similar to FIG. 7 illustrating an adjustment in the stroke of the actuating lever.

In the drawings, FIG. 1 illustrates an embodiment of the invention comprising an infeed conveyor 10 which frictionally advances a line of abutting articles a, across.

' functional elements, briefly illustrates what is well known to those skilled in the art concerning such wrapping machines. With the exception of special purpose machines, it is conventional practice to provide for wrapping a fairly wide range of article sizes on a single machine. The rate of operation of the machine is, to a large extent, governed by the stroke of the elevator, which in turn is determined by the height of the tallest article to be wrapped. Thus, with an elevator rate of cycles per minute and a 12" stroke for an 8" high article, the same stroke would be employed for an article 1'' high and little or no increase in operating rate would be possible.

The present invention provides means for adjusting the elevator stroke and in so doing maintaining a constant upper or discharge position to which the elevator is reciprocated in each cycle of operation. Also, means are provided for adjusting the height of the infeed conveyor 10 to align it with the lower or receiving position of the elevator 14. The elevator reciprocating mechanism and stroke adjusting means are later described in detail.

In FIG. lthe adjusting mechanism is represented by a knob 18. The height of the infeed conveyor 10 is adjusted to the lower position of the elevator 14 by jack screws 20 (only one of which is shown).

With the elevator reciprocating through a shorter stroke, it is then possible to increase the rate of operation of the elevator and the wrapping machine as well. Conveniently, a common motor M, or other power source, may be employed to drive the wrapping machine, the elevator reciprocating mechanism and the infeed conveyor 16. By employing a variable speed drive 22, it is a simple matter to increase or decrease the speed of operation of these elements in proper timed relation, as the elevator stroke is increased or decreased. It is thus possible to obtain maximum operating rates and maximum efliciency for a given article height.

With reference to FIG. 2, a somewhat dilferent application of the invention will be described. Again, an infeed conveyor 40 advances articles a across a dead plate 41 to an elevator 42, which is reciprocated by mechanism 44. The elevator 42 receive the leading article from conveyor 40 in its lower or receiving position and then raises that article to latches 46 in its upper or discharge position. The elevator 42 is then lowered to receive a subsequent article from conveyor 40 which is next raised to the latches 46 to assemble a stack of articles thereon.

Patented Mar. 29, 19%6.

After a predetermined number of reciprocations of the elevator 42 (which determines the number of layers in the stack) the assembled stack is advanced by a pusher 48 to a conveyor 50 which then advances the stack of articles to a wrapping machine or the like, indicated at 51.

The above briefly describes operation of a stacking device, as shown in copending application Serial No. 343,191, filed February 4, 1964, and reference is made thereto if further details are desired.

In FIG. 2 knob 52 corresponds to knob 18 above and is provided to adjust the reciprocating mechanism 44 to obtain the minimum stroke necessary for a given height of article, again maintaining the upper position of the elevator a constant relative to the latches 46. Jack screws 56 are provided for adjusting the height of the feed conveyor 49. Preferably, a mechanical connection is made between the knob 52 and the jack screws 56, so that these adjustments are made simultaneously to maintain the level of the conveyor 40 at all times in proper relation to the lower position of the elevator 42 regardless of the stroke thereof.

Again a variable speed drive 57 may be employed in combination with motor M to obtain maximum rates of operation of the stacking device for any given height of article being stacked. A mechanical connection may be provided between the knob 52 and the variable speed drive so that the speed of the stacking device is at all times at its maximum effective rate.

In the stacking device, it is desirable to vary the number of layers in a stack, therefore it is desirable to vary the number of strokes of the elevator 42 relative to each stroke of the pusher 48. Without varying any other adjustment, this end may be attained by the use of change gears 58 which control the rates of the elevator reciprocating mechanism relative to that of the pusher 48 independently of all other factors. 7

In either embodiment, the elevator reciprocating mechanism 16 or 44 may take the form seen in FIGS. 3-8. First having reference to FIG. 3, an elevator mounting post 60 is connected to a pair of parallel links or arms 62, 64- by pins 66, 68 respectively. The lower arm 64 is pivotally mounted on a pin 70 projecting from a vertical plate 72 which comprises a portion of a main bracket 73 for this mechanism. The upper arm 62 is secured by clamp screw 74 to a shaft 76, which in turn is journaled (see also FIG. at its ends on the frame plate 72 and a second frame plate 78 parallel thereto. The plate portions 72 and 78 are connected by a strengthening web 80.

Either elevator 14 or 42 may be mounted atop post 60 for vertical reciprocating movement through a slightly curved path by reason of the parallel linkage mounting therefor which comprises the arms 62, 64.

Movement is imparted to this linkage through a lever 82, which is connected by pin 84 to a downwardly offset projection 86 of arm 62. The lever 82 is slidably received intermediate its length in a block 88, which is pivotally mounted on a stud 90 projecting from a slide 92. The slide 92 is received in a horizontal guideway formed on the frame plate 72 and comprises a guide plate 94 secured thereto by screws 96. An adjusting screw 98 is threadably received by the slide 92 and journaled in fixed axial position in a bracket 100 which is secured to the frame plate 72. The knob 19 (or 52) is secured to the screw 98 so that the position of slide 92 in guideway 94 may be readily adjusted which, in turn, varies the stroke of post 60, as will later be made apparent.

The opposite end of lever 62 is pivotally connected by pin 102 to a block 104 which receives a vertical link 106. In normal operation there is no relative movement between link 106 and block 104 so that the arm 62 may be considered as being pivotally connected directly to the link 106. The block -4 forms part of an overload detection means for sensing any jam which would interfere with reciprocation of the elevator. A plate 108 is secured to the block 106 and has a limit switch 110 mounted thereon. The plunger of this limit switch is aligned with a pin 112 which is slidable in the block 104. The inner end of the pin 112 is normally maintained in a groove formed in the link 106 by spring 114 to provide a detent connection between the link 106 and the block 104.

The link 106 is normally reciprocated to oscillate the arm 62, however, in the event a jam prevents free movement of the arm 62, pin 112 will be displaced from the groove in link 106 to actuate the switch 110. The switch 110 is incorporated in the electrical control circuit of the machine to immediately halt operation of the motor M so that damage to the machine components or the articles will be prevented or minimized.

The lower end of link 106, FIGS. 4 and 6, is pivotally connected by pin 116 to one end of a lever 118. The opposite end of lever 118 is pivotally mounted by pin 120 on an upstanding boss 122 on the main frame 73. A two diameter cam follower 124 is rotatably mounted on the lever 118 intermediate its length for engagement with a cam 126 of known design which has appropriate peripheral surfaces engaging the follower 124 to impart oscillatory movement to the lever 118 in proper timed relation.

The cam 126 is secured to a shaft 128 which is journaled in a third vertical frame plate 130 and also the frame plates 72 and 78. The shaft 28 is rotated through the change gears 58 disposed outside the frame plate 78 and removably secured to the shaft 128 and a jack shaft 136. The latter shaft is journaled in the frame plates 72 and 78 and has a second gear 138 (FIG. 4) secured thereto and meshing with a gear 140. The latter gear is secured to a shaft 142 which is journaled in boss 144, 146 projecting upwardly from the main frame 73.

A bevel gear 148 meshes with a bevel gear 150 secured to an appropriately journaled shaft 152. Sprocket 154 ecured to the opposite end of the shaft 152 is connected to the variable speed drive 22 (or 57) through means comprising a chain 156 trained therearound. A second sprocket 158 is secured to the shaft 152 and drives the infeed conveyor 10 (or 40) through a chain 160.

In normal operation the cam rotates continuously to oscillate the lever and thus to oscillate lever 82 through link 106. Lever 82 oscillates about the axis of stud 90 and is free to slide in the guide 88 as oscillatory motion is transmitted to arm 62 to reciprocate the elevator mounting post 60.

The slide 92 is shown in its position for greatest elevator stroke. As it is adjusted toward the opposite end of guideway 94, the length of the stroke is progressively decreased. This is best illustrated in FIGS. 7 and 8, which show the slide 92 in its two extremes of adjustment. In each instance it will be noted that the portion of the arm 82 received by :block 88 is horizontal and parallel to the path of adjustment of slide 92 (stud 80 is actually the more important component) when the elevator post 60 is in its upper position. This relationship insures that the upper position of the elevator will be a constant regardless of its stroke which may be infinitely varied. The angular relationship of the left hand end of lever 82 is to enable the force exerted by link 106 thereon to be substantially tangent to the stud 90 throughout its stroke.

Having thus described the invention, what is claimed as novel and desired to be secured by Letters Patent of the United States is: V

1. In combination with a machine having an elevator reciprocable between a lower article receiving position and an upper article discharge position, a feed conveyor for advancing articles onto said elevator in its article receiving position, means for reciprocating said elevator between said positions, means for varying the stroke of said reciprocating means with the level of said elevator at the discharge position being a constant, means for adjusting the level of said conveyor commensurate with the adjustment in the stroke of the reciprocating means to properly feed articles onto said elevator in any given article receiving position and means for varying the rate of operation of said machine so that the rate of operation may be progressively increased as the stroke of said elevator is decreased.

2. In combination with a machine having an elevator reciprocable between a lower article receiving position and an upper article discharge position, a feed conveyor for advancing articles onto said elevator in its article receiving position, means for reciprocating said elevator between said positions, said reciprocating means comprising an actuating lever, means connecting one end of said actuating lever to said elevator, a guideway in which said actuating lever is slidable, said guideway being pivotally mounted, means for oscillating said actuating lever about the pivot axis of said guideway to reciprocate said elevator, and means for adjusting the position of the pivotal axis of said guideway along a path parallel to said lever when the elevator is in its upper position, whereby the stroke of the elevator will be varied with a fixed oscillating stroke of the actuating lever while at the same time maintaining the upper position of said elevator a constant, and means for adjusting the level of said conveyor commensurate with the adjustment in the stroke of the reciprocating means to properly feed articles onto said elevator in any given level of the article receiving position.

3. In combination with a machine having an elevator reciprocable between a lower article receiving position and an upper article discharge position, a feed conveyor for advancing articles onto said elevator in its article receiving position, means for reciprocating said elevator between said positions, said means comprising a parallel linkage mounting including a pair of parallel arms and a vertical post surmounted by the elevator, an actuating lever connected at one end to said parallel linkage, a guideway in which said actuating lever is slidable, said guideway being pivotally mounted, means connected to the opposite end of said actuating lever for oscillating said lever with a fixed stroke about the pivotal axis of said guideway to reciprocate said elevator, said actuating lever being displaced to a given position in the upper discharge position of said elevator, and means for adjusting the position of the pivotal axis of said guideway along a path parallel to said lever in said given position whereby the stroke of the elevator will be varied with a fixed oscillating stroke of the actuating lever, while at the same time maintaining the upper position of said elevator a constant, and means for adjusting the level of said conveyor commensurate with the adjustment of the stroke of the reciprocating means to properly feed particles onto said elevator in any given level of the article receiving position.

4. A combination as in claim 3 wherein common drive means are provided for said machine and for the means for oscillating said actuating lever, and further wherein change gear means are provided in the drive for oscillating said actuating lever whereby the number of reciprocations of said elevator per machine cycle may be readily varied 5. Elevator reciprocating mechanism comprising an actuating lever, means connecting one end of said actuating lever to the elevator, a guideway in which said actuating lever is slidable, said guideway being pivotally mounted, means for oscillating said actuating lever about the pivotal axis of said guideway to reciprocate said elevator and means for adjusting the pivotal axis of said guideway along a path parallel to said lever when the elevator is in its upper position whereby the stroke of the elevator will be varied with a fixed oscillating stroke of the actuating lever while at the same time maintaining the upper position of said elevator a constant.

6. Elevator reciprocating mechanism comprising a parallel linkage mounting including a pair of parallel arms and a vertical post surmounted by the elevator, an actuating lever connected at one end to said parallel linkage, a guideway in which said actuating lever is slidable, said guideway being pivotally mounted, means for oscillating said actuating lever about the pivotal axis of said guideway to reciprocate said elevator and means for adjust; ing the pivotal axis of said guideway along a path parallel to said lever when the elevator is in its upper position whereby the stroke of the elevator will be varied with the fixed oscillating stroke of the actuating lever, while at the same time maintaining the upper position of said elevator a constant.

7. Elevator reciprocating mechanism comprising a parallel linkage mounting including a pair of parallel arms and a vertical post surmounted by the elevator, an actuating lever connected at one end to said parallel linkage, a guideway in which said actuating lever is slidable, stud means on which said guideway is pivotally mounted, a guide block carrying said stud means, a link connected to the opposite end of said actuating lever, a control lever pivotally connected to said link at one end and pivotal about a fixed axis at the opposite end, and cam means controlling oscillation of said control lever to thereby oscillate said actuating lever about said stud means and thus reciprocate said elevator, and means for adjusting said block and the stud means carried thereby along a path parallel to said lever when the elevator is in its upper position whereby the stroke of the elevator will be varied without modification of the cam means while at the same time maintaining the upper position of said elevator a constant.

References Cited by the Examiner.

UNITED STATES PATENTS 2,883,032 4/1959 Leaman et al 198-24 EVON C. BLUNK, Primary Examiner.

WILLIAM B. LA BORDE, EDWARD A. SROKA,

Examiners. 

1. IN COMBINATION WITH A MACHINE HAVING A ELEVATOR RECIPROCABLE BETWEEN A LOWER ARTICLE RECEIVING POSITION AND AN UPPER ARTICLE DISCHARGE POSITION, A FEED CONVEYOR FOR ADVANCING ARTICLES ONTO SAID ELEVATOR IN ITS ARTICLE RECEIVING POSITION, MEANS FOR RECIPROCATING SAID ELEVATOR BETWEEN SAID POSITIONS, MEANS FOR VARYING THE STROKE OF SAID RECIPROCATING MEANS WITH THE LEVEL OF SAID ELEVATOR AT THE DISCHARGE POSITION BEING A CONSTANT, MEANS FOR ADJUSTING THE LEVEL OF SAID CONVEYOR COMMENSURATE WITH THE ADJUSTMENT IN THE STROKE OF THE RECIPROCATING MEANS TO PROPERLY FEED ARTICLES ONTO SAID ELEVATOR IN ANY GIVEN ARTICLE RECEIVING POSITION AND MEANS FOR VARYING THE RATE OF OPERATION OF SAID MACHINE SO THAT THE RATE OF OPERATION MAY BE PROGRESSIVELY INCREASED AS THE STROKE OF SAID ELEVATOR IS DECREASED. 